Merck & Co. Inc.'s (MRK) blockbuster cancer drug Keytruda is again at the FDA altar, awaiting approval for yet another indication on October 30, 2020.The proposed indication of Keytruda this time is as monotherapy for the treatment of adult patients with relapsed or refractory classical Hodgkin lymphoma (cHL). Hodgkin lymphoma is a type of lymphoma that develops in the white blood cells called lymphocytes, which are part of the immune system. Classical Hodgkin lymphoma accounts for more than nine in 10 cases of Hodgkin lymphoma in developed countries.Keytruda as monotherapy or in combination with other medicines is already approved for the treatment of Melanoma, Metastatic, Non-Small Cell Lung Cancer, Head and Neck Cancer, Hodgkin's Lymphoma, Urothelial Carcinoma, Gastric Cancer, Cervical Cancer, Hepatocellular Carcinoma, Merkel Cell Carcinoma, Renal Cell Carcinoma, Small Cell Lung Cancer, Esophageal Carcinoma, Endometrial Cancer, and Squamous Cell Carcinoma.The drug recorded global sales of $11 billion for full year 2019 and $3.37 billion in the first half of this year. MRK closed Friday’s (Sep.25, 2020) trading at $82.93, down 0.26%.